Wire Nuts, Parallel Batteries and other thoughts

[Alphacarina]

I can see your point about dissimilar metal contact from the metal inside a wire nut (only some wire nuts), but if that is the argument against, then what makes a crimp on connector different, as it also places "metal against wire?
If the tinning of the wire prevents it, that is good, but the act of crimping could easily remove some of the tinning.
If you crimp on a connector, and then tin, how can it get under the connector to provide complete coverage?

Most marine wiring is made using tinned wire and most crimp connectors are tinned as well

I've been wiring and redoing the factory wiring on sailboats for a number of years and I solder every connection I crimp just to ensure a good connection - Don't think it's 'required' . . . . it's just something I do so I don'tget any callbacks. It's a REALLY good idea to solder them if you're notusing tinned marine wire. I began many years ago soldering every connection in the bilge, as there are more wiring failures for bilge pumps than any other single thing and it worked out so well I just started soldering everything

Wire nuts have a sharp coil of metal in them that's not usually copper and it's purpopse is to gouge a groove in the conductors to ensure a good mechanical connection . . . . I think the electrical connection comes from compressing the twisted bundles of wire - But I'm no expert on wire nuts, so take that with a grain of salt - Not too much salt or you'll ruin your wire nut connection

If I had to use a wire nut, I would finish it off by forcing a dab of silicone sealant in the end to seal the wires and nut into an airtight 'bubble' . . . . something you could never accomplish even with a mile of electrical tape

Don

[48Rob]

Thanks Don,

I can see using soldered connections in a damp place, and especially a damp place filled with salt!
Some heat shrink tubing might be good too, as an added backup for connections that may end up underwater!

When I was learning general construction wiring, I was taught the the wire nut simply protects the connection from shorting against the box.
That the wires better darn well be twisted together well enough not to come apart, even if there is no wire nut...or I'd be looking for another job!

Though not common, the further back in age you go when working on rehab projects, the more of those "secure" connections you find.

I've not ever used silicone for sealing a wire connection, but do use antioxidant paste wherever moisture is a concern.
I suppose silicone would work just as well, as anything that keeps the air away is an antioxidant, but life wouldn't be any fun if I couldn't get that nasty black paste all over everything.

Rob

PS. Some wire nuts have a coil of metal, but not all!